SSD's are in (Crucial X300's father than the Sandisks I ordered before, because they couldn't deliver despite promising next day shipping so I cancelled the order and got these). Damned thing won't boot from the striped set, even though the OS is installed and i can navigate the volume from the terminal.

Netflix upping the subscription prices for the… sixth(?) time in just over two years or something, making my subscription now twice the price it was when I signed up, prompted me to long for the good old days of pirating my media rather than paying for them.

So, since I finally had some time on my hands, I got a few steps further with this thing. The RAID0 won't budge; not with Terminal, not with Disk Utility, not in 10.7, not in High Sierra. Much Googling led to the last resort solution: open up the box, disconnect one of the drives, reboot, format the remaining drive, reconnect the second drive, reboot. That effectively destroys the RAID, thus prompting macOS to release it for formatting.

Anyway, with a fresh High Sierra install and a single Crucial MX300 256GB SSD APFS boot volume:

Wowzers. A five-fold increase in disk speed. Niiiice. Now to set up the second drive and try and coax the bloody thing into RAID0'ing, again.

Well, a day wasted tinkering and googling leads to the inevitable conclusion that APFS and/or High Sierra don’t play nice with AppleRAID. Apple’s (sparse) information on the subject is contradictory, suggesting that APFS simply isn’t quite as ready for prime time as one would hope. So the Mini will have to chug along with two single SSD’s, for now. Bummer.

Apple did make a big deal about APFS, but mostly for iOS devices and portables. It might be plausible that RAID support is not exactly on their radar, unless I'm mistaken in that the iMac Pro indicates a skewed understanding of what professionals actually want in a pro computer.

(11-21-2017, 02:09 PM)FuturDreamz Wrote: Apple did make a big deal about APFS, but mostly for iOS devices and portables. It might be plausible that RAID support is not exactly on their radar, unless I'm mistaken in that the iMac Pro indicates a skewed understanding of what professionals actually want in a pro computer.

I think I’m going to have to read up on the nitty-gritty of APFS. Tell us, Conan, isn’t the APFS model ultimately supposed to be agnostic to an underlying RAID structure? I’m not yet quite up on the container-volume lingo.

Quote:SoftRAID will have an update available, hopefully at the same time as 10.13 is released.

We do not plan on offering APFS support in this update.

SoftRAID will be bootable for 10.13.

When we are able to support APFS for SoftRAID volumes, then, yes, we still anticipate being able to support encryption.

We cannot say much more at this time.

APFS is far more than just a new file system. APFS is an entirely new metaphor on what a volume is, what a folder is, what a file is, and where files are actually located. It opens up a complexity that will baffle experienced users. We are working on how to best simplify this complexity to users.

Here is a simple example:
Create a couple APFS volumes, on different disks. Make them small enough to perform the following experiment:
1. Copy a large DMG file to the first volume. Duplicate it several times, until > 50% of the volume "should" be filled. (It won't show this, however. The volume will not show any decrease in capacity.)
2. Open each DMG, and copy a small file into it, then close it. Each DMG is now "unique".
For example, lets say it is a 500GB volume and each DMG is 200GB.
As part of the example, consider you duplicated the DMG 3 times and edited each one.
Your first volume will show 200GB used, 300GB free.
3. Now, try to copy the data to the second volume, you will get an error, not enough free space.

Even the most experienced Mac user can be baffled by this when it happens to them.

And this is just the tip of the complexity iceberg that APFS brings to the Mac.

Can you just not use APFS? Or do you not have a choice? Can't you just format as the old journaled format?

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The issue is with the High Sierra installer; it flat out refuses to install (or upgrade) to a RAID set. The formatting is irrelevant. Word of God (well, someone close, anyway) is that they dropped support for installing macOS to RAID sets, although it is unclear whether this is temporary.

On the other hand, Apple report that they (will) support APFS on RAID, but the information is scarce enough that it is not clear whether they mean hardware or software RAID. AppleRAID is supported in APFS in the sense that Disk Utility can create an APFS RAID though the command line, but not through the GUI. Either I’m doing something wrong, or it’s still buggy, though.

The workaround to having a RAID High Sierra system volume (whether JHFS+ or APFS) is to install to a regular volume, then clone to the RAID. I could do that, install to an SD card, clone to the RAID then import my setup from Time Machine. Problem is, I would have to do that for every system update, presumably, until AppleRAID becomes properly supported in High Sierra. I’m still pondering whether I’m willing to bother.

The end goal for my server setup is to run a couple of server VM’s within a hypervisor, so the point will become moot as the hypervisor should take care of the RAID and the VM’s will be none the wiser, the (virtual) drives will just be fast.

(11-22-2017, 02:58 AM)Alien Wrote: I think I’m going to have to read up on the nitty-gritty of APFS. Tell us, Conan, isn’t the APFS model ultimately supposed to be agnostic to an underlying RAID structure? I’m not yet quite up on the container-volume lingo.

Yeah, APFS should be totally transparent from that standpoint. If it were still the weird amalgam of HFS+ and CoreStorage, I could see the issue (that they've had years to work through and for the most part, have), but from an APFS perspective, it shouldn't be a big issue.

Then again, they haven't really got Fusion drives working yet either, so maybe there's more skullduggery at the implementation level than I suspect.

Well, I have some time to kill, today, and I just received four 64GB MicroSD cards that are destined for my trusty iPod Classic, so I figured I give the workaround a go.

High Sierra is now installing (excruciatingly slowly, I might add) to an APFS formatted SD card. Once that's done, I'll create the APFS RAID0 again on the SSD's, and clone the system from the SD onto the RAID. I've heard tell that this is the way to get High Sierra to run from a RAID set. Fingers crossed.

I'm not sure I want to run a production server thusly, because it will require going through the entire process every time the system needs updating, but now it's personal and I need to know what kind of drive performance the RAID0 would show.

Once we move to the new house, I'm thinking of getting me one of these bad boys:

Four ten-core Xeons and eight 2.5" bays should make for all the computing power and storage I need to run a bunch of virtual machines, these things go for peanuts on the used market.

That's what happens when you boot High Sierra from a MicroSD card. Not recommended.

Anyway, I got the OS installed on a said SD card, then reconstructed the RAID stripe. Took some fiddling; High Sierra disk Utility only creates HFS+ RAIDs, but luckily, there's still the Terminal.

Next step was to clone the system drive to the RAID. Disk Utility refuses to clone the active system volume. Command line cloning (asr) seems to have been gimped in High Sierra. So, boot into System Recovery and clone the SD to the RAID, right? Wrong. Apparently, Apple are so vehemently against installing High Sierra on a RAID, that they actively hide RAID sets from the System Recovery version of Disk Utility. So, destroy the RAID, create a HFS+ RAID in DU, manually mount it, repartition the thing to APFS, then, finally it'll let me clone the SD to the RAID. That didn't take long.

And wouldn't boot.

So I gave up. I figure there's reasons Apple go to such lengths to bar one from installing High Sierra on a RAID, and the experience with booting from the SD was so unenjoyable, I am seriously dreading having to do that every time I need to install a security update, and to be left gambling whether or not the thing will start from the RAID after each update. I'm just disappoint that I didn't get to do a disk speed test on the RAID, that would've been fun. Oh well.

Well, since it doesn’t look like Apple will be adding RAID support to APFS any time soon, I’m considering a different strategy. Maybe they’re working on a RAID-Z like approach, maybe they’ve just given up on RAID altogether. Whatever, Apple.

Running macOS High Sierra from an APFS-formatted SD, with the twin SSD’s configured as a RAID-0 data drive. HFS+, if necessary, but preferably APFS. I posted above that using an SD for a boot drive sucks, which it does, but I suppose I can mitigate that with some trickery.

First on the list would be user space. This is easy; just relocate all user directories to the SSD’s. Other things that would impact overall performance are: swap, time machine snapshots, sleep images, and temp directories. Am I missing anything? Input is welcomed.

I might have to get another Mac mini as I’m not that keen on trying all this out on my “production” machine. Luckily, prices on non-Mojave-capable mini’s have plummeted.